Molecular sieves are classified by the Structure Commission of the International Zeolite Association according to the rules of the IUPAC Commission on Zeolite Nomenclature. According to this classification, framework type zeolites and other crystalline microporous molecular sieves, for which a structure has been established, are assigned a three letter code and are described in the “Atlas of Zeolite Framework Types,” Sixth Revised Edition, Elsevier, 2007.
One known molecular sieve for which a structure has been established is the material designated as EUO, which is a molecular sieve having a one-dimensional microporous framework, with channels having a diameter of 4.1×5.4 Å, with large lateral side pockets. According to N. A. Briscoe et al. (Zeolites, 1988, 8, 74-76), the lateral pockets have a depth of 8.1 Å and a diameter of 6.8×5.8 Å. Molecular sieves with the EUO framework type include EU-1, TPZ-3, and ZSM-50.
U.S. Pat. No. 4,537,754 discloses zeolite EU-1 and its synthesis using a dicationic alkylated polymethylene diamine as a structure directing agent.
U.S. Pat. No. 4,695,667 discloses zeolite TPZ-3 and its synthesis using an N,N,N,N′,N′,N′-hexamethyl-1,6-hexane diammonium cation as a structure directing agent.
U.S. Pat. No. 4,640,829 discloses zeolite ZSM-50 and its synthesis using a dibenzyldimethylammonium cation as a structure directing agent.
U.S. Pat. No. 7,431,913 discloses the synthesis of EUO framework type zeolites in the presence of an N,N-dimethyl-N,N-di(3,3-dimethylbutyl)ammonium cation as a structure directing agent.
U.S. Pat. No. 8,038,982 discloses the synthesis of EUO framework type zeolites using an alkyl quinuclidinium cation as a structure directing agent.
It has now been found that pure phase EUO framework type molecular sieves can be prepared using an N,N′-dimethyl-1,4-diazabicyclo[2.2.2]octane dication as a structure directing agent.